The act of calling bullshit: When one person says something that another person is not in agreement with, that second person may "call bullshit" on whatever the first person said. By doing this, they are expressing their disagreement with what the person said in a humorous and yet serious way.
Person1: "Of course I don't drink! I'm not 21 yet so that's illegal."

Me:" Umm sorry, but I call bullshit on that. I was with you last night at that frat party and you were far from the perfect little sober college student you're pretending to be right now."
by Fuckin' Bullshit March 22, 2011
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1. to call one out on a complete flasehood

2. an expression of distaste or aggrivation

3. to have found something at odds with a generally accepted truth
1. "i am the coolest person in the world"
"i call bullshit"

2. "we've got a 15 page paper due tommarow boyo, and it has to be written entirely in sanskrit"
"i call bullshit"

3. "george w. bush is a great president"
"i call bullshit"
by thought of this years ago October 1, 2006
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To point it out when one is lying. In certain situations it may be used to refer to an unfair system or an outcome of such a system.
"I love you."
"I call bullshit. You're just trying to get laid."
Men get paid more than women. I call bullshit!
by Ioulia called it! March 5, 2009
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